Sealed motor compressor unit



Sept. 26, 1939. w. K. BODY ET AL 32,174,233

SEALED MOTOR COMPRESSOR UNIT Filed Sept. 1, 1957 3 Sheets-Sheet lINVENTORS. 'W ZZZZdn; /i ,BqJz,

Savzzzz] Z6 [a Sept. 26, 1939. w. K. BODY Er AL 2,174,233

SEALED MOTOR COMPRESSOR UNIT Filed Sept. 1. 195'! a Sheets-Sheet 2m'zzzzdm z SazzzyzzeZ zi'fizzfii MWW Sept. 26, 1939. w. K. BODY ET AL2,174,233

SEALED MOTOR COMPRESSOR UNIT Filed Sept 1, 19s? ssheets-sheet s v M (32v p N 4 as /55 I y b x /fl w: 6'6 22' E u /04' E I MEMO/5- 14 Z! L427;hf ,504

By 5427342162 22 ,B'zc Zea Patented Sept. 26, 1939 PATENT OFFICE SEALEDMOTOR COMPRESSOR UNIT William K. Body, Detroit, and Samuel E. Bickle,

Highland Park, Mich., assignors to Borg-Warner Corporation, acorporation of Illinois Application September 1, 1937, Serial No.161,950

6 Claims.

This invention relates to refrigeration, A and particularly to smallcapacity refrigerating machines of the compression type which aresuitable for household use and has forlts object to provide apparatus ofthe character designated which shall operate reliably, quietly andefliciently. It has for a further object the provision of arefrigerating machine which shall be compactly arranged and which shallhave its mechanism entirely sealed within a unitary structure to preventescape of the working fluid.

A further novel feature of the invention resides in the relativearrangement of the compressor and condenser which are so located as tofacilitate circulation of air thereabout and hasten the transfer of heatfrom these two bodies to the atmosphere. With this object in view, thecondenser is placed below the motor-compressor unit so as to cause arising current of air to sweep both of these objects, the air beingcaused to rise by being heated by these bodies.

As will be recognized, the preferred embodiment of the invention residesin an electric motor and a compressor located within a sealed casing andadapted to be positioned within a refrigerator cabinet with the electricmotor positioned above the compressor. The compressor-condenser assemblyis supported from a frame which is attached to the frame of therefrigerator cabinet as a unitary structure and is so constructed thatit occupies a very small space therein.

Means are also provided for withdrawing oil from a bath in which thecompressor operates and circulating such oil to the various parts of thecompressor, such oil being ultimately returned to the bath or reservoir.

Still further objects will be' observed as the description proceeds andin connection with the appended claims.

In the accompanying drawings, in which like reference characters areemployed to indicate similar parts, and which are to serve as an exampleand not to be considered as limiting the invention;

Fig. 1 is a diagrammatic view of the refrigerating system showingsomewhat in detail the compressor and the condenser in plan view;

Fig. 2 is an elevational view of the compressor condenser assembly;

Fig. 3 is a vertical sectional view of the motorcompressor;

Fig. 4 is a bottom plan view of the motor-compressor taken onsubstantially the plane indicated by the line 4--4 of Fig. 3 and lookingin the direction of the arrows, but omitting the bottom cover plate ofthe compressor casing;

Fig. 5 is a sectional view taken substantially on the plane indicated bythe line 5--5 of Fig. 4 looking in the direction of the arrows; 5

Fig. 6 is a sectional view taken substantially upon the plane indicatedby the line 6--6 of Fig. 4 and looking in the direction of the arrows;

Fig. 7 is a sectional view taken substantially upon the plane indicatedby the line 1'! of Fig. 3 and looking in the direction of the arrows.

Referring first to Fig. 1, the refrigerating system will be seen tocomprise a motor-compressor unit I0 which serves to compress gaseousrefrigerant, said refrigerant being discharged through conduit l2 whenceit passes through the convolutions of condenser I4 to become a liquidand into receiver l6 through conduit ll. The liquid refrigerant inreceiver "5 is withdrawn through conduit l3 and is discharged into theevaporator 20 (located in space to be cooled) through an expansion valveor some other type of metering device (not shown);

Within the evaporator the refrigerant boils and absorbs heat from theenvirons of the evaporator and changes from a liquid to a gaseous state.The gaseous refrigerant is returned by conduit 22 to the compressor I0where the cycle begins anew. A control 24 is provided which isresponsive to changes in temperature within the refrigerated compartmentand is adapted periodically to close and open the circuit 26 to thecompressor motor from the usual domestic electrical supply line.

A structural steel frame 28 made up of strap members 30 and curved crossmembers 32 secured together is provided for supporting the compressorand condenser. Clips 34 connected to the condenser frame 36 are attachedto the strap members 30 by means of bolts 38. Curved cross members 32support lugs 40 which are slotted at their upper ends to receive aspring 42 for resiliently supporting the motor-compressor 10. Thereceiver I6 is supported by members 39 secured to the frame 28 andcondenser Hi.

The condenser l4 comprises a series of parallel tubes 44 connected attheir ends by headers 46 and intersected throughout their length bytransversely extending fins 48.

Refrigerant being discharged from the compressor l0 enters the condenserI4 after passing through a circular loop 50 in the discharge line. Thegeneral flow of refrigerant within the condenser is from right to leftas viewed in Figs. 1 and 2 and, in order to provide proper drainage ofall liquid components of the refrigerant with- In the condenser, thecondenser is sloped downwardly to the left as viewed in Fig. 2. Thereceiver may also be slightly sloped downwardly from its intake end toits outlet end as illustrated at I5 in Fig. 2.

The motor-compressor I5 comprises in general an outer casing 52 whichmay be of pressed steel. (See Fig. 3.) Press fitted into the interior ofcasing 52 is a frame element 54 for a stator 55 of an electric motor.Stator 55 may be made up of a plurality of core laminations connectedtogether by rivets or bolts 55 and windings 55 extending thereabout forinducing magnetism in the stator 55. A laminated rotor 52 having a hub54 is pressed onto the upper portion of a shaft 55 spllned at 55 toreceive the hub 54.

The spider 15, arranged within the interior of casing 52, may beprovided witha circular peripheral portion which abuts the lower edge ofstator frame 54. The peripheral portion of spider may be provided with aseat II for receiving the lower edge 15 of the stator frame 54. The seat1i and the lower edge 15 provide complementaryinterfitting aligningsurfaces so that the stator frame 54 and spider 15 may be assembled,prior to the assembly thereof with the casing 52, which makes itpossible to test the compressor while the parts are still accessible toan inspector. The spider 15 may be secured to the stator frame 54 by aplurality of bolts H, the ends of which are threaded into threadedopenings 12' formed in lugs 15' carried by the stator frame 54. Thecasing 52 is relieved at 15 so as to facilitate assembly of spider 15and stator frame 54 with thecasing 52. Hie central portion of spider 15extends upwardly at 12 to provide bearings 14 and 15 in which shaft 55is rotatably mounted. Spider 15 is also provided with a flat downwardlypresented surface 15 which forms the upper wall of the cylinder 55 ofthe compressor. A plate or cylinder block 52, provided with acylindrical bore 54 concentrio with respect to bearings 14 and 15, isarranged below spider 15, and a third plate 55 forms the bottom wall ofthe cylinder 55. These parts and a valve cover plate 55 are securedtogether by cap screws 55.

Shaft 55 is provided on its lower end with an eccentric portion 52,which rotatably receives a roller or rotor 54 which is operativelyassociated with the top and bottom walls of the cylinder 55 and with thecylindrical wall of bore 54. Eccentric 52.bears upon bottom plate 55 ofthe cylinder 55 and thereby supports the rotor 52 of the electric motorand the weight of shaft 55.

The clearance provided between the rotor 54 and the top and bottom wallsof the cylinder 50 is extremely small, being in the nature of only a fewten thousandtbs of an inch. A similar clearance exists between the rotorand the cylindrical wall of bore 54. These clearances in operation arespanned by a film of lubricant which serves to prevent leakage of therefrigerant therethrough.

Gaseous refrigerant returning from the evaporator through suction line22 enters the motorcompressor unit I5 through a gland 55 provided inlower cover member 55, such cover member being fitted into the interiorof casing 52 and welded thereto along adjacent flanged edges as at I55.Suction line 22 enters valve plate 55 (Fig. 5) through a fitting I52provided therein. The gaseous refrigerant is conducted through astrainer I54 and discharged upwardly through port I55 in plate 55 nearthe upper surface of which there is provided a check valve I55. Valve I55 is seated at IIII upon valve plate 55 and is pressed by spring I I2into engagement therewith.

Refrigerant passing valve I55 is admitted to cylinder 55 through a portII4.

Rotation of eccentric 52 (Fig. 3) causes rotor 54 to be progressivelyassociated with the wall of bore 54. A blade II5 (Figs. 4 and 7) extendsinto the cylinder through a slot H5 in block 52 and engages the rotor 94for separating the high and low sides of the compression chamber. BladeH5 is urged in the direction of the rotor 54 by spring I25 seated in arecessed portion I22 of the blade H5 and bearing against a clip I24secured to the lower surface of spider 15 by screws I25. Refrigerantcompressed within cylinder 55 is discharged downwardly through port I25(Fig. 6) in lower plate 55. Plate 55 has a valve seat I55 formed on itslower surface about port- I25 and a flapper valve I52 is operativelyengaged therewith. Valve l52 is maintained In seating relation to seatI55 by,,means of its own resiliency and screw I54.

The compressed refrigerant is discharged into a pocket I55 in valveplate 55 from which point it passes upwardly through a. port I25 formedin cylinder forming members 15, 52 and 55. A section of tubing I45leading from the port I55 in plate 15 discharges the compressedrefrigerant into the space defined by shield I45, where it impingesuponbaiile ring I42 prior to escaping through the annular aperture I45and holes in baiiie ring I44. Baffle rings I42 and I44 may be secured tothe hub 54 of the rotor 52 in any suitable manner while ring I45 issecured as at I41 to the top surface of spider 15 to provide a reservoirI51 for lubricant.

The compressed refrigerant may flow upwardly through holes I55 providedin the rotor 52 and is discharged from the casing 52 through a fittingI52 and discharge line I54. Fitting I52 is tapped at I55 to receive a.plug I55 which has sealing engagement with a washer I50. Dust cap I52,having sealing engagement with a washer I54, is provided for coveringplug I55. In order to charge the compressor the dust cap I52 may beremoved and replaced by a charging fitting (not shown). Plug I55 is thenbacked out until port I55 is clear of the threaded portion and thedevice may be charged. After charging, the procedure is reversed and thedust cap I52 returned 1 to its original position.

Lubricant I51 collects within the shield member' I to about the levelindicated by the line I55, the shield member forming a reservoir forsuch lubricant. The lubricant I51 is subjected to the relatively highpressures existing within the casing 52 and is forced through port I15to the vicinity of eccentric 52 and rotor 54 where it accumulates inclearance space I 12. A spiral groove I14 formed in the eccentric 52carries lubricant I61. downwardly from clearance space I12 to lubricatethe eccentric formal bearing and the thrust bearing between the end ofeccentric 52 and plate 55 from which the lubricant is carried through aport I15 formed in the bottom plate 55 to a sump I15 in valve plate 55.As the oil accumulates in this sump, it flows laterally through a slotI55 formed in the upper face of the valve plate 55 to a port I52 throughthe three cylinder forming members and is returned to the lubricantreservoir.

The lubricant in clearance space I12 is also withdrawn therefrom bymeans of a spiral groove I84 formed in the bearing I4 and is movedupwardly thereby to clearance space I86 from which point it is carriedto the top of bearing I6 by means of a spiral groove I88 formed therein.The lubricant spills over the top of bearing I6 through space I90 and isreturned past the baiiie plate I42 to the oil reservoir.

The lubricant in clearance II2, being subjected to the dischargepressure, also flows outwardly between the small clearances existingbetween the rotor 94 and the walls of the cylinder to provide the sealpreviously referred to. Such lubricant as is carried out of the cylinderwith the compressed gas is, in the main, removed by contact with thebaffles I42, I44 and I46, whence it is returned to the reservoir.

Any lubricant which may happen to find its way outside of ring memberI46 is also subjected to the high pressure existing within the casing 52and, accumulating in the bottom of the easing 52, is forced by suchpressure through the minute clearances existing between the platemembers of the compressor and between the blade H6 and the blade slotand ultimately finds its way back to the reservoir. The oil charge issufficient to insure overflow of shield member I46 and the maintenanceof the oil level above cylinder 82 and the blade slot therein.

The exterior of casing 52 may be provided with radially disposed fins I92 for dissipating heat generated within the casing. A clamp I94 may beprovided on such fins for retaining the suction line in place. Clips I96welded to fins I92 are apertured and bushed as at I98 to receivesupporting springs 42 extending from frame members 40.

Leads 200 (Fig. 4) from the motor extend to bolts 202 which pass throughcover member 98. Fittings 204 (Fig. 3) serve to receive bolts 202 whichfunction as binding posts, and bushings 206 and washers 208 ofinsulating material insulate the connections from the casing 52.

It will thus be seen that a highly compact and a readily assembledstructure has been provided which by reason of the intimate contact ofthe main internal portions thereof with the casing will readilydissipate heat generated in the casing to the atmosphere. It will alsobe noted that the moving parts of the compressor and motor are supportedby a single member through which 011 is adapted to be circulated andthat the compressor will operate with a very small quantity of oil dueto the peculiar construction of the oil reservoir.

While the invention has been described in considerable detail, it is tobe expressly understood that the description given is for the purpose ofillustration only and is not definitive of the limitations of theinventive idea. The right is reserved to make such changes in thedetails of construction and arrangement of parts as fall within thescope of the appended claims.

We claim:

1. In a refrigerating system, a sealed motorcompressor unit, a framehaving resilient connections extending to and supporting said unit, anda condenser rigidly mounted on said frame below said unit, said framemember having legs extending below said condenser and having crossmembers for supporting said motor-compressor unit which presents theirsmallest area to air rising through said condenser and around saidmotor-compressor unit.

2. In a refrigerating apparatus, a sealed motorcompressor unit, a framehaving resilient connections extending to and supporting said unit, anda condenser rigidly mounted on said frame below said unit, said framecomprising horizontal members which define a generally ring-shaped frameof larger diameter than said motor-compressor unit and to whichring-shaped frame said resilient connections are mounted.

3. In a refrigerating system, a sealed motorcompressor unit, ahorizontal frame having resilient connections extending to said unit forsupporting the unit, a condenser rigidly mounted on said frame belowsaid unit, and a receiver rigidly secured to the frame above the lowerend of the condenser, said horizontal frame having leg portionsextending below said connections and arcuate cross members supportingsaid. re silient connections in spaced relationship with saidmotor-compressor unit.

4. In a refrigeration system, a motor and a compressor contained in asealed casing, a planar condenser located below said casing andpositioned at an acute angle with respect to a horizontal plane, theinlet to the condenser being located at the high point thereof and theoutlet therefrom being located at the low point thereof, a receiverlocated over the low point of said condenser, the longitudinal axis ofsaid receiver being sloped downwardly with respect to the horizontalfrom intake to outlet, and a frame for supporting said motor andcompressor unit and said condenser and receiver, said frame comprisingcross members with bent-down legs at either end and two arcuate members,said condenser being supported between said bent-down legs by means ofclips, and said motor-compressor unit being supported from said arcuatemembers by means of clips extending above said arcuate members.

5. Refrigerating apparatus including a planar condenser arranged in aninclined plane, a frame carried thereby and including a pair of spacedhorizontally arranged strap members, curved cross members carried bysaid strap members and vertically extending lugs carried by said crossmembers, a sealed motor compressor unit resiliently carried by saidvertical lugs and connected to'said condenser for supplying compressedrefrigerant to the upper part thereof, a part of said condenser beingarranged at a lower elevation than said unit.

6. Refrigerating machinery comprising a motor-compressor unit, acondenser and a receiver, a frame for supporting said receiver,condenser and motor-compressor unit comprising two cross members havingbent-down legs at either end thereof, two oppositely curved cross piecesfastened between said cross members, said curved cross pieces carryingvertical lugs slotted at their upper end for receiving spring mounts forsaid motor-compressor unit, and clips attached to the legs of said crossmembers for supporting a condenser.

1 WILLIAM K. BODY.

SAMUEL E. BICKLE.

